Board of Regents Chairman Merryl Tisch is spot-on in pushing to double the number of charter schools in New York state. It could mean a big chunk of federal cash — and, incidentally, it’s just the right thing to do.

Still, she’s strolling in a political minefield.

Tisch’s plan includes hiking the cap on charters from 200 to 400, increasing the money going to them and allowing test scores to be used for teacher assessment.

All this would help New York qualify for the Obama Department of Education’s “Race To The Top” funding.

Under the initiative, states get access to a $4.35 billion pool of education grants from the federal stimulus package.

New York could receive as much as $700 million — and what a tonic that would be.

In theory, the pathway to the dough is pretty clear:

* Write a plan that fulfills the federal requirements.

* Legislate whatever “reforms” are needed to get Washington’s OK.

* Collect the dough.

So far, so good.

But Tisch has supported charters long enough to know that getting true charter-friendly reform through Albany won’t be that easy. Not by a long shot.

The state Senate is in chaos. As for the Assembly, Tisch needs to understand that Speaker Sheldon Silver’s true agendas historically are sharply at odds with what he says they are.

Trust but verify, as a wise man once said in another context. For, as soon as the feds look away, the foot-dragging on the reforms will begin.

And nobody’s being coy about it.

After learning of Tisch’s plan, new United Federation of Teachers boss Michael Mulgrew promptly declared that, before lifting the charter cap, “We must make sure that all students have access to all schools.”

That’s impossible, of course.

And because the UFT calls most of the shots regarding charters, Tisch needs to consider herself fairly warned.

She’s playing table-stakes poker — and she needs to take great care that the deck isn’t stacked.